mISDN: Do not disable IRQ in ph_data_ind()
This fix triggering the WARN_ON_ONCE(in_irq() || irqs_disabled()); in
local_bh_enable().
Here is no need to grab this lock, this was wrong at all and may
cause a deadlock and access to freed memory, since on a TEI remove
the current listelement can be deleted under us. So this is clearly
a case for list_for_each_entry_safe.
Signed-off-by: Karsten Keil <keil@b1-systems.de>
diff --git a/drivers/isdn/mISDN/tei.c b/drivers/isdn/mISDN/tei.c
index bfcdd97..e04bad6 100644
--- a/drivers/isdn/mISDN/tei.c
+++ b/drivers/isdn/mISDN/tei.c
@@ -862,8 +862,7 @@
ph_data_ind(struct manager *mgr, struct sk_buff *skb)
{
int ret = -EINVAL;
- struct layer2 *l2;
- u_long flags;
+ struct layer2 *l2, *nl2;
u_char mt;
if (skb->len < 8) {
@@ -908,11 +907,9 @@
new_tei_req(mgr, &skb->data[4]);
goto done;
}
- read_lock_irqsave(&mgr->lock, flags);
- list_for_each_entry(l2, &mgr->layer2, list) {
+ list_for_each_entry_safe(l2, nl2, &mgr->layer2, list) {
tei_ph_data_ind(l2->tm, mt, &skb->data[4], skb->len - 4);
}
- read_unlock_irqrestore(&mgr->lock, flags);
done:
return ret;
}